Exopolymer matrix

A biofilm is commonly visualized as a two-dimensional matrix layered on a solid surface. However, aggregates of exopolymer, detritus, and cells also form in the water column through a variety of physical, chemical, and biotic processes (Ward et al., 1994 Grossart et al., 1997 Chapter 12). These aggregates are variously described as floes or snow . A type of aggregate... 

Polymeric nature of the triofilm matrix (exopolymers) that can prevent antimicrobial agents from reaching bacteria inside the biofilm. 

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